244 University of California Fuhlications in Agricultural Sciences [Vol. 1 



surface foot. The underlying whitish limy loam seems to have 

 restricted the development of plant roots to the upper four feet. 

 The humus is also poor in nitrogen and was probably derived 

 from the meager roots of sage and alkali weeds. 



A soil previously taken from the Susanville ]\Ieadows had 

 only 0.33 per cent of humus, and another from two miles west of 

 Amedee had but 0.29 per cent. 



Madaline Plains. — Passing north from Honey Lake Valley 

 across hills covered with beds of lava, we come to the Madaline 

 Plains, which occupy an immense and almost level basin (prob- 

 abl.y once an inland lake) at an elevation of 5200 feet above sea- 

 level. Its area is approximately 150 square miles, very irregular 

 in outline, and bordered on all sides by lava hills. Its soil is 

 a dark and very compact clay, underlaid at three or more feet 

 by a light-colored marl of a hardpan nature and upwards of 

 seventy-five feet in thickness, as shown in well-borings. A column 

 of this soil four feet in depth was obtained from the plain to 

 the westward of the place of W. C. Brockman. Previous analyses 

 of other samples show fair amounts of phosphoric acid. Grass 

 and grain are said to do w^ell on this plain. The surface foot was 

 found to contain 0.52 per cent of humus, and the second foot 

 0.60 per cent, but below this the clay was almost free from it. 

 The soil contains about 0.04 per cent of humus-nitrogen. 



Pitt Eivcr Valley. — Pitt River, with its source at the western 

 foot of the Warner range of mountains, passes through a number 

 of valleys as it tiows westward into the Sacramento Eiver. The 

 to-v^Ti of Alturas is located in one of these valleys at the junction 

 of the two forks of the river. The soil of the valley is chiefly 

 meadowland with water at a depth of a few feet and partly 

 grown in tules, but affording large alfalfa tracts. A column of 

 six feet was taken from an alfalfa field near the town. The 

 valley is bordered by lava-beds and hills. Goose Lake Valley to 

 northward and reaching into Oregon has a similar meadowland 

 soil reaching from the lake eastward to the foot of the mountains, 

 where the disintegrated debris affords some higher land on which 

 orchards are planted. 



Klamath Lake Marshes. — A column from the tule marshes of 

 Klamath Lake, Butte Valley, was obtained for us by ]\Ir. L. S. 

 Robinson for examination. 



